HTTP协议的请求与数据抓包

import java.io.IOException;
import java.net.Authenticator;
import java.net.InetSocketAddress;
import java.net.PasswordAuthentication;
import java.net.Proxy;

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;


public class Demo
{
    // 代理验证信息
    final static String ProxyUser = "username";
    final static String ProxyPass = "password";

    // 代理服务器(产品官网 www.16yun.cn)
    final static String ProxyHost = "t.16yun.cn";
    final static Integer ProxyPort = 31111;

    // 设置IP切换头
    final static String ProxyHeadKey = "Proxy-Tunnel";


    public static String getUrlProxyContent(String url)
    {
        Authenticator.setDefault(new Authenticator() {
            public PasswordAuthentication getPasswordAuthentication()
            {
                return new PasswordAuthentication(ProxyUser, ProxyPass.toCharArray());
            }
        });
        // 设置Proxy-Tunnel
        Random random = new Random();
        int tunnel = random.nextInt(10000);
        String ProxyHeadVal = String.valueOf(tunnel);

        Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress(ProxyHost, ProxyPort));

        try
        {
            // 处理异常、其他参数
            Document doc = Jsoup.connect(url).timeout(3000).header(ProxyHeadKey, ProxyHeadVal).proxy(proxy).get();

            if(doc != null) {
                System.out.println(doc.body().html());
            }
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }

        return null;
    }

    public static void main(String[] args) throws Exception
    {
        // 要访问的目标页面
        String targetUrl = "http://httpbin.org/ip";


        getUrlProxyContent(targetUrl);
    }
}